In a data storage system, a filesystem typically is stored on a volume provided by the data storage system. In some advanced data storage systems, the volume on which the filesystem is stored is a sparse metavolume populated by data storage slices of a fixed size provisioned from a pool of slices. The pool of slices aggregates slices provided by storage volumes, known as Flare LUNs (FLUs). A system having a similar arrangement is described in further detail in U.S. Pat. No. 8,285,758, the contents and teachings of which are hereby fully incorporated herein by this reference.
Under various conditions, such as in response to a corruption event, a slice consistency check is performed in order ensure that each slice is properly assigned to the appropriate sparse metavolume and filesystem. The slice consistency check involves ascertaining the ownership of each slice in the system according to (1) a software layer responsible for allocating slices from the FLUs, (2) a slice map maintained by a software layer responsible for managing the sparse metavolume, and (3) a set of linked slice marks maintained by the software layer responsible for managing the sparse metavolume.